The present invention relates to a transmission mechanism for a magnetic damping type step machine which uses transmission wires and pulleys to turn a flywheel between reversed directions alternatively.
Various magnetic damping devices are known, and widely used in body building apparatus (or more specifically in standing bicycles). Chinese Patent No. 167,914 discloses a magnetic damping control mechanism for an exercising machine which comprises a gear wheel mounted on the machine base and driven by two pedals, a belt wheel mounted on the machine base at the front and linked to the gear wheel by a chain, and a flywheel driven by the belt wheel through a transmission belt, and a device disposed below the flywheel and controlled to provide a magnetic damping resistance to the flywheel. FIG. 1 illustrates a step machine which is approximately similar to the structure of the aforesaid magnetic damping mechanism for an exercising machine. Because the pedal has a limited moving range, the gear wheel is turned in either direction through a limited angle, and therefore the revolving speed of the flywheel is limited. Because the revolving speed of the flywheel is limited, the cutting resistance from the electromagnetic device is relatively small. Therefore, an additional control device must be used to regulate electric current to the electromagnetic device. This arrangement simultaneously complicates the structure of the machine and also increases its cost. Further, because the gear wheel and the belt wheel are respectively mounted on the machine base at two opposite ends, the size of the machine can not be reduced.